GRB 201029A

S. Dichiara (NASA/GSFC/UMCP), J. A. Kennea (PSU),
N. J. Klingler (PSU), S. Laha (GSFC/UMBC/CRESST),
F. E. Marshall (NASA/GSFC), M. J. Moss (GWU),
K. L. Page (U Leicester), D. M. Palmer (LANL),
A. Tohuvavohu (U Toronto) and E. Troja (NASA/GSFC/UMCP) report on
behalf of the Neil Gehrels Swift Observatory Team:

At 20:19:50 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 201029A (trigger=1003002).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 229.601, +44.464 which is 
   RA(J2000) = 15h 18m 24s
   Dec(J2000) = +44d 27' 50"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single complex peak
structure with a duration of about 40 sec.  The peak count rate
was ~1800 counts/sec (15-350 keV), at ~5 sec after the trigger. 

The XRT began observing the field at 20:21:52.3 UT, 122.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 229.58280, 44.45975 which
is equivalent to:
   RA(J2000)  = 15h 18m 19.87s
   Dec(J2000) = +44d 27' 35.1"
with an uncertainty of 3.5 arcseconds (radius, 90% containment). This
location is 49 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper. No
spectrum from the promptly downlinked event data is yet available to
determine the column density. 

The initial flux in the 2.5 s image was 7.42e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 131 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02. 

Burst Advocate for this burst is S. Dichiara (dichiara AT umd.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)

Martin Jelinek, Jan Strobl (ASU CAS Ondrejov, CZ),

Sergey  Karpov, Martin  Masek,  Petr  Janecek, Jakub  Jurysek,
Jan  Ebr, Ronan  Cunniffe, Petr  Travnicek and  Michael Prouza
(Institute of Physics, Prague, CZ)

report:

The  25cm  robotic  telescope  FRAM-ORM at  La  Palma  (Spain)
reacted  robotically   to  the   Swift  alert   of  GRB201029A
(trigger=1003002; Dichiara  et al.,  GCNC 28803),  obtaining a
series of 20s unfiltered images starting at 20:21:23.0UT, i.e.
93s post trigger.

We do not  detect any new source in the  XRT error box neither
in single  images (3-sigma  limit R>~15.7)  nor in  a combined
20x20s frame (mean  exp time 276s post  trigger, 3-sigma limit
R>~18.15) similarly to Lipunov et al. (GCNC 28804).

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 764 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 201029A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 229.58157, +44.45927 which is equivalent
to:

RA (J2000): 15h 18m 19.58s
Dec (J2000): +44d 27' 33.4"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.

Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado (IAA-CSIC),  C. Perez del Pulgar,  A. Castellon, I. Carrasco, A. Reina (Univ. de Malaga) and F. Rendon (IAA-CSIC and INTA-CEDEA) on behalf of a larger collaboration, report:

Following the Swift trigger of GRB 201029A (Dichiara et al., GCNC 28803), the 0.3m BOOTES-1B robotic telescope in Mazagon (Huelva), southern Spain, automatically responded to this burst at 8 degrees above the horizon. Series images were taken started 20:21:26UT (~96 s after trigger). In the co-added of following images, no source is detected within the enhanced XRT position (Beardmore et al., GCNC 28806) which down to 17.7 mag (clear filter), which consistent with the non-detections reported by UVOT (Dichiara et al., GCNC 2828803) and FRAM-ORM (Jelinek et al., GCNC 28805).

We thank the staff at INTA-CEDEA for their excellent support.

M. Perri (ASDC), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), B. Sbarufatti
(PSU), D.N. Burrows (PSU), J. D. Gropp (PSU), K.L. Page (U. Leicester),
A.P. Beardmore (U. Leicester) and S. Dichiara (NASA/GSFC/UMCP) reporton
behalf of the Swift-XRT team:

We have analysed 6.2 ks of XRT data for GRB 201029A (Dichiara et al.
GCN Circ. 28803
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 ), from 128 s to 34.7 ks after the  BAT trigger. The
data comprise 764 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Beardmore et al. (GCN Circ. 28806
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 ).

The light curve is dominated by flares. The first flare covers
~T0+200-650 s. The second flare started at T0+1100s and was still
ongoing when the GRB entered Earth eclipse at T0+1850 s. The third
flare began at T0+11.5 ks, was still ongoing at T0+23 ks and finished
at some point before T0+30.5 ks, although large observing gaps in this
window prevent acccurate measurements of the flare and it is possible
that there are multiple flares at this time rather than a single
long-lived flare. This behaviour, of multiple flares dominating the XRT
light curve for tens of kiloseconds, is reminiscent of GRBs 050904,
121027A and 130925A (see
https://www.swift.ac.uk/xrt_curves/allcurves.php for a mugshot gallery
of all XRT GRB afterglows).

This flaring activity makes it difficult to model the underlying
behaviour. Excluding all of the above times, the light curve can be
modelled with a power-law decay with a decay index of alpha=0.79
(+0.05, -0.06). These formal errors are likely underestimates, since
they depend on how accurate the estimates of flare times are, which are
themselves subject to proper modelling of the underlying emission.

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	 of 1.65 (+/-0.05). The
best-fitting absorption column is  4.9 (+/-0.3) x 10^21 cm^-2, in
excess of the Galactic value of 2.1 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.97 (+/-0.12) and a
best-fitting absorption column of 2.9 (+/-0.5) x 10^21 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.7 x 10^-11 (5.4 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     2.9 (+/-0.5) x 10^21 cm^-2
Galactic foreground: 2.1 x 10^20 cm^-2
Excess significance: 9.6 sigma
Photon index:	     1.97 (+/-0.12)

If the light curve continues to decay with a power-law decay index of
0.79, the count rate at T+24 hours will be 0.024 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.2 x
10^-13 (1.3 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team
automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01003002.

This circular is an official product of the Swift-XRT team.

P. Veres and C. Meegan (both UAH)
report on behalf of the Fermi GBM Team:

"At 20:19:51.61 UT on 29 October 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 201029A (trigger 625695596 / 201029847)
which was also detected by the Swift/BAT (Dichiara et al., GCN 28803
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 ).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 59 degrees.

The GBM light curve consists of a broad peak
with a duration (T90) of about 78 s (50-300 keV).
The time-averaged spectrum from T0-8.2 s to T0+34.8 s is
adequately fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.03 +/- 0.10 and
the cutoff energy, parameterized as Epeak, is 647 +/- 230 keV.

The event fluence (10-1000 keV) in this time interval is
(1.59 +/- 0.14)E-5 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.4 s in the 10-1000 keV band
is 1.4 +/- 0.2 ph/s/cm^2.



The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"

F. E. Marshall (NASA/GSFC) and S. Dichiara (NASA/GSFC/UMCP)

report on behalf of the Swift/UVOT team:



The Swift/UVOT began settled observations of the field of GRB 201029A

131 s after the BAT trigger (Dichiara et al., GCN Circ. 28803
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 ).

No optical afterglow consistent with the XRT position

(Beardmore et al. GCN Circ. 28806
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 )

is detected in the initial UVOT exposures.

Preliminary 3-sigma upper limits using the UVOT photometric system

(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first

finding chart (FC) exposure and subsequent exposures are:



Filter         T_start(s)   T_stop(s)      Exp(s)         Mag



white_FC           131          281          147         >20.6

u_FC               289          539          246         >19.9

white              131         1708          412         >21.4

v                  619         1759          127         >19.2

b                  545         1858          136         >19.9

u                  289         1833          362         >20.0

w1                 842         1808           97         >19.5



The magnitudes in the table are not corrected for the Galactic extinction

due to the reddening of E(B-V) = 0.02 in the direction of the burst

(Schlegel et al. 1998).

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev, O.Ershova 
(Irkutsk State University, API),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich, Yu. Sergienko 
(Blagoveschensk Educational State University)




MASTER-IAC robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Spain (IAC Teide Observatory) was pointed to the Swift GRB 201029A ( S. Dichiara et al., GCN 28803
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 ) errorbox 103 sec after trigger time at 2020-10-29 20:23:35 UT, with upper limit up to  17.3 mag. The observations began at zenith distance = 77 deg. The sun  altitude  is -27.6 deg. 

The galactic latitude b = 56 deg., longitude l = 73 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1471870

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

     113 |          MASTER-IAC |   C |    20 | 15.9 |        
     148 |          MASTER-IAC |   C |    90 | 16.6 |  Coadd 
     338 |          MASTER-IAC |   C |   470 | 17.3 |  Coadd 
     146 |          MASTER-IAC |   C |    30 | 16.0 |        
     197 |          MASTER-IAC |   C |    40 | 16.0 |        
     253 |          MASTER-IAC |   C |    50 | 16.3 |        
     343 |          MASTER-IAC |   C |   230 | 17.0 |  Coadd 
     322 |          MASTER-IAC |   C |    60 | 16.4 |        
     672 |          MASTER-IAC |   C |   120 | 16.5 |        
     817 |          MASTER-IAC |   C |   150 | 16.6 |        
     997 |          MASTER-IAC |   C |   510 | 16.6 |  Coadd 
     993 |          MASTER-IAC |   C |   180 | 16.4 |        
    1193 |          MASTER-IAC |   C |   180 | 16.4 |        
    1392 |          MASTER-IAC |   C |   180 | 16.1 |        
    1572 |          MASTER-IAC |   C |   540 | 16.6 |  Coadd 
    1591 |          MASTER-IAC |   C |   180 | 16.0 |        
    1791 |          MASTER-IAC |   C |   180 | 15.9 |        
    1991 |          MASTER-IAC |   C |   180 | 15.7 |        
    2601 |          MASTER-IAC |   C |   180 | 15.3 |        
   83049 |          MASTER-IAC |   C |    60 | 16.8 |        
   84836 |          MASTER-IAC |   C |    60 | 16.5 |        
   85552 |          MASTER-IAC |   C |    60 | 16.6 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.

S. Laha (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), S. Dichiara (NASA/GSFC/UMCP),
H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-60 to T+243 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 201029A (trigger #1003002)
(S. Dichiara et al., GCN Circ. 28803
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 ).  The BAT ground-calculated position is
RA, Dec = 229.607, 44.473 deg which is
   RA(J2000)  =  15h 18m 25.7s
   Dec(J2000) = +44d 28' 21.7"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 96%.

The BAT light curve showed a complex structure with a duration of about 150 sec.
T90 (15-350 keV) is 120.55 +- 9.54 sec (estimated error including systematics).

The time-averaged spectrum from T-2.19 to T+133.11 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.09 +- 0.11.  The fluence in the 15-150 keV band is 2.2 +- 0.1 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+7.06 sec in the 15-150 keV band
is 0.6 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1003002/BA/